2015 Exploring the influence of ancient and historic megaherbivore extirpations on the global methane budget
https://www.pnas.org/content/113/4/874.short

Here, we quantify one potential effect of the decline of large herbivores: the reduction of the greenhouse gas methane released as a byproduct of plant digestion. We examine three time periods where large-scale losses of megaherbivores occurred—the African rinderpest epizootic of the 1890s, the massive Great Plains bison kill-off in the 1860s, and the terminal Pleistocene extinction of megafauna. We find detectable decreases in the global methane budget related to the extirpation of megaherbivores. Our findings underscore the importance of large mammals in regulating ecosystems and feedbacks on climate.

...

Using global datasets of late Quaternary mammals, domestic livestock, and human population from the United Nations as well as literature sources, we develop a series of allometric regressions relating mammal body mass to population density and CH4 production, which allows estimation of methane production by wild and domestic herbivores for each historic or ancient time period. We find the extirpation of megaherbivores reduced global enteric emissions between 2.2–69.6 Tg CH4 y−1 during the various time periods, representing a decrease of 0.8–34.8% of the overall inputs to tropospheric input. Our analyses suggest that large-bodied mammals have a greater influence on methane emissions than previously appreciated and, further, that changes in the source pool from herbivores can influence global biogeochemical cycles and, potentially, climate.

2017 Integrating Herbivore Population Dynamics Into a Global Land Biosphere Model: Plugging Animals Into the Earth System
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2016MS000904

In this study, we coupled herbivore population dynamics in a global land model (the Dynamic Land Ecosystem Model, DLEM 3.0) to simulate populations of horses, cattle, sheep, and goats, and their responses to changes in multiple environmental factors at the site level across different continents during 1980–2010. Simulated results show that the model is capable of reproducing observed herbivore population dynamics across all sites for these animal groups. Our simulation results also indicate that during this period, climate extremes led to a maximum mortality of 27% of the total herbivores in Mongolia. Across all sites, herbivores reduced aboveground net primary productivity (ANPP) and heterotrophic respiration (Rh) by 14% and 15%, respectively (p lower than 0.05). With adequate parameterization, the model can be used for historical assessment and future prediction of mammalian herbivore populations and their relevant impacts on biogeochemical cycles. Our simulation results demonstrate a strong coupling between primary producers and consumers, indicating that inclusion of herbivores into the global land modeling framework is essential to better understand the potentially large effect of herbivores on carbon cycles in grassland and savanna ecosystems.

Agriculture must change, with different skills and a new attitude required | MinnPost
https://www.minnpost.com/...riculture-must-change-with-different-skills-and-a-new-attitude-required/

For Earth to remain viable for human habitation for more than a few decades, agriculture must change.

It must give up its centuries-old fascination with annual crops like wheat and corn, and begin the study of how perennial plants fit food production. Perennial plants, properly managed as under a good planned grazing regimen, incorporate atmospheric carbon into the soil as organic matter, thus beginning to reverse centuries of burning off carbon through tillage. Even carefully planned rotations of annual plants without tillage will not safeguard soil and build organic matter like a good stand of perennials.

Perennial plants must be developed for food production instead of this shortsighted focus on breeding plants that can withstand chemical applications. Wes and Dana Jackson established the Land Institute, a nonprofit research center in Salina, Kansas, in 1976, and have been working on perennial replacements for annual crops ever since. They and their staff developed Kernza from intermediate wheatgrass, useful for both grazing and its wheat-like kernel. It is currently being distributed and commercialized by the University of Minnesota with the help of certain grain milling and baking businesses. Another ongoing study is of Illinois Bundleflower, a potential protein source for livestock and humans.

Production of perennial crops requires close on-site management driven by observation, experience and a feel for natural systems. This is especially evident for Kernza production, which is best done by a mix of cropping and livestock systems. We have few people in the farm population even capable of this breadth of management anymore. A different set of farming skills and a new attitude are required. It will take both time and financial stability to learn them, and then to apply them. The need for decision-making based upon observation and knowledge of place and its biology presupposes that operations cannot be huge. Perennial agriculture will create a different human social structure around it.

GOJATLA: 403 forbidden link

TADEAS: tyhle studie jakoby nemuzou bejt guideline, protoze se nepphybujou analyticky v prostoru tech kyzenejch reseni. jako kdyz se nemuzes rozhodnout jestli jadro nebo plyn nebo uhli, napr. protoze dí myslis ze nic jinyho neni relevantni. je to zavadejici uhel pohledu

Na závěr roku 2020, aspoň jedna dobrá zpráva:
GM Reintroduces Hummer As Fully Electric Truck, 1st Model Will Sell For $112,595
https://www.npr.org/...ummer-as-fully-electric-truck-1st-model-will-sell-for-112-595?t=1608732681921